Who was not already in the shop and felt overwhelmed by the sheer infinite selection of stoves? You are helplessly standing there and do not know at all the difference between the models and fuels, or where to start …
Depending on the type of used fuel trekking stoves can be sorted like this:
- liquid fuels
- gasoline for automobiles
- pure gasoline
- solid fuels
- burning paste
- Spiritus tablets (Esbit)
To find the right stove, we recommend starting with the fuel and its properties.
Would you like to do a tour where you know the duration in advance?
Then you can roughly estimate how many times per day you will cook and how much water or liquid you need to heat up. Consequently, in this case, it makes the most sense to orientate oneself on the consumption of the fuel. If you know how much fuel you consume, you can pretty much estimate how much you need to take with you.
If, on the other hand, you intend to travel indefinitely – or for a very long period time– then you should compare the fuels in particular in the price. The costs of the different fuels vary enormously.
The pack size and the weight always play a role and should be considered accordingly.
In addition, depending on the destination, you should also think about the availability of the fuel.
Of course, there are other factors such as:
But more on that later …
Comparing stoves and their fuels is no easy task.
The calorific value (stored energy per kg) is often used here.
However, as a starting point, this value is not particularly helpful because many stoves differ in performance and other characteristics with the same fuel. Cooking habits and environmental influences also affect the performance of the stove and thus also on the consumption.
A good example here is alcohol (29.7 MJ / kg) vs. Esbit (31.3 MJ / kg). The higher energy density suggests that Esbit is the better fuel. In practice, however, shows a different result: Despite higher fuel value and lower consumption per minute you need more Esbit than alcohol to bring one liter of water to a boil.
So in order to make a statement for consumption, you have to do an investigation!
Of course, my little investigation is by no means complete. To actually be able to make valid statements, a much larger number of digesters would have to be tested. In order to determine a rough tendency, however, the study should be suitable.
Here is a list of different stoves in different cooking scenarios, all with the task of bringing 1 liter of water to boil.
I am particularly interested in the average fuel consumption.
Now you can see a first tendency, in which the LPG in the consumption is quite different from the other tested fuels.
The price is ultimately about the cost per cooked food.
In order to have a basis here, I use the price per firing minute.
Of course, you could also use the price per liter (if you exclude the solid fuels) which would make things much easier. However, you would do not consider the efficiency of the stove and the general consumption of the fuel.
In addition, the entire cooking process plays a role and not only the time until the water boils. The background to this is that with gasoline, diesel, petroleum, kerosene and spirit stoves, the combustion chamber first has to be heated so that the fuel can be gasified. Of course, this process costs time and fuel, which can not or only inefficiently be used for cooking.
In addition, the fuels unfold their full power only after a certain time.
petrol stoves after 1:30 min
and alcohol stoves after around the 3 min
Finally, there is the time to burn the fuel line empty.
Of course, you can use this time for cooking without any restrictions, but it takes some experience.
Other factors influencing consumption and thus are the design of the stove, the pot, and additional equipment.
These may be the following variables
- Size of the flame relative to the pot
- heat conductor
- The material of the pot
- heat reflectors
In my investigation, it turned out that the stoves differ relatively little with their fuels in the current consumption. Depending on the situation, the consumption per firing minute fluctuates strongly between 0.93g (moderately turned up) and 4.8g (without windscreen), but I would say that the determination of the average of all test situations will help here the most.
Although this number is not exact, it can be useful as a rough guideline.
With a 10 to 15min cooking, unit results in the following ranking
- wood (free)
- 1l diesel (1.25 € – 1.35 €) with about 20 to 30 cooking units (1l equivalent to 830g)
- 1l petrol (1,40 € – 1,60 €) with about 18 to 27 cooking units (1l equals 750g)
- 200g fuel paste (0.75 €) with about 5 to 8 cooking units
- 1l alcohol (4 €) with about 19 to 29 cooking units (1l corresponds to 790g)
- 1l petroleum (5 €) with about 19 to 29 cooking units (1l equals 800g)
- 1 liter of pure gasoline (6 €) with about 18 to 27 cooking units
- 450g LPG cartridge (9 €) with about 11 to 16 cooking units
- 125g LPG cartridge (5 €) with about 3 to 5 cooking units
- Esbit pack 12 * 14g (7 €) with theoretically 4 to 6 cooking units (a little bit out of as the burning time per tablet ends after 12min)
When it comes to fuel procurement, you do not always have to think of distant foreign countries.
Because some fuels are hard to find, even in your own town.
- Fuels, which are used in a car, can be found at every gas station
- You should look for fuel paste, alcohol, and pure gasoline in some food discounters, outdoor sports shops, and hardware stores.
- Petroleum is most likely to be found in hardware stores.
- Esbit tablets are commonly found in outdoor sports shops and hardware stores.
- With LPG, you have to look more closely, because not every cartridge is suitable for every stove. And not every cartridge is available everywhere. Basically, you can divide the cartridges into 3 types, which are usually found in outdoor sports shops and hardware stores
- pierceable cartridges
- screwable cartridges
- bayonet cartridges
- For the wood it is easy! You might think! But you should note that there are vegetation limits, weather and seasons, which can make it difficult to find useful fuel.
What role safety plays, you only realize when it affects you.
However, you do not have to kick around the stove first to see if the fuel creates a problem or not.
There are also aspects such as:
- risk of explosion
- Flashpoint and ignition temperature
- health compatibility
- or other things that cause them to be taken off the plane.
Reliable fuels are fuels that ignite anytime, anywhere and, at best, have little impact on performance.
Low temperatures, wind, and humidity are environmental factors that make life difficult for the fuel.
However, you should never underestimate the complexity of the stove. “the more features it has, the more can break”.
But it is also true that manufacturers are already putting a lot of effort into improving the reliability of all stoves.
Which is why most of them only use high-quality materials.
LPG however, will no longer gaseous and alcohol is difficult to ignite.
Although solid fuels such as wood, Esbit, and fuel paste do not have any problems with cold, their performance in the case of humidity drops sharply. A problem that does not matter with cartridges or bottles.
Wind affects all fuels and stoves negatively. Although some manufacturers have been coming up with intelligent solutions for some time (e.g., MSR).
But a simple and inexpensive windscreen is usually sufficient to shield the flame.
The peculiarities of combustion are related to the design of the stove, as well as to the fuel itself.
A big issue here is the soot formation. You see a sooty fuel, apart from the black residue on the outer pot bottom, on a yellowish-red flame. The discoloration occurs when carbon glows but does not burn completely. This results in the formation of soot.
What can be done to minimize soot formation?
- Increase flame temperature
(many stoves allow to adjust the oxygen-fuel mixture so the stove can be controlled)
- Dilute the fuel
(a method to put a stop to quite heavy sooting alcohol) Caution this will decrease the calorific value!
- Optimize the oxygen supply
(if there is too little oxygen, the fire smolders and cannot burn properly. If the flame flickers, the air flow is not optimal, which again leads to an unclean combustion)
By the way: No other fuel burns so cleanly like LPG.